Thickness Dependence of Ferroelectric and Optical Properties in Pb(Zr0.53Ti0.47)O3 Thin Films

Abstract

As a promising functional material, ferroelectric Pb(ZrxTi1−x)O3 (PZT) are widely used in many optical and electronic devices. Remarkably, as the film thickness decreases, the materials’ properties deviate gradually from those of solid materials. In this work, multilayered PZT thin films with different thicknesses are fabricated by Sol-Gel technique. The thickness effect on its microstructure, ferroelectric, and optical properties has been studied. It is found that the surface quality and the crystalline structure vary with the film thickness. Moreover, the increasing film thickness results in a significant increase in remnant polarization, due to the interfacial layer effect. Meanwhile, the dielectric loss and tunability are strongly dependent on thickness. In terms of optical properties, the refractive index of PZT films increase with the increasing thickness, and the photorefractive effect are also influenced by the thickness, which could all be related to the film density and photovoltaic effect. Besides, the band gap decreases as the film thickness increases. This work is significant for the application of PZT thin film in optical and optoelectronic devices.

Band Gap of Pb(Fe0.5Nb0.5)O3 Thin Films Prepared by Pulsed Laser Deposition

“…We therefore conclude, from the comparison of the UV-Vis spectroscopy with the UPS/IPES data, that the absorption edge observed at ~2.3 eV (2.25 eV) likely originates from defect levels in the band gap, while the absorption at ~2.78 eV (2.75 eV) corresponds to the fundamental band gap. It was reported in the literature that the band gap value in PZT or PLZT films depends on the film thickness, while no clear trend has been found [39][40][41]. In our case, the band gap for the 100 nm thin films is comparable with the data for the bulk PFN, where the value of 2.67 eV was measured.…”

Non‐Volatile Reconfigurable p–n Junction Utilizing In‐Plane Ferroelectricity in 2D WSe2/α‐In2Se3 Asymmetric Heterostructures

“…On the other hand, ferroelectric materials are promising as a non‐volatile, energy‐efficient, reconfigurable source of an electric field. While conventional ferroelectrics such as LiNbO 3 , [ 14 ] HZO, [ 15 ] and BFO [ 16 ] demonstrate stable electrostatic doping when combined with 2D materials, they suffer from strong depolarization with thickness reduction, [ 17 ] interfacial defects due to surface reconstruction, and fatigue. [ 18 ] Therefore, the fabrication of atomic‐scale ferroelectric films with uniformly aligned polarization is still challenging.…”